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Welcome to Edition 2.16 of the Rocket Report! It's been a busy week in space, with the launch of the first person from the United Arab Emirates as well as the final launch of a venerable Russian rocket. By my favorite story this week is a recollection by Wayne Hale about one contingency NASA never had to put in place with the space shuttle—a crew member riding home in the payload bay.

As always, we welcome reader submissions, and if you don't want to miss an issue, please subscribe using the box below (the form will not appear on AMP-enabled versions of the site). Each report will include information on small-, medium-, and heavy-lift rockets as well as a quick look ahead at the next three launches on the calendar.

Blue Origin to conduct two more uncrewed test flights. The company expects to fly its New Shepard space tourism rocket at least two more times before it puts the first people on board, Chief Executive Bob Smith said this week. This probably will necessitate a slip into 2020 for the first crewed flights, CNBC reports.

What is driving the delays? ... "It's really the robustness of our entire system. It's not one individual thing that's driving [these delays]," Smith said. "It's us being cautious and thorough with the total systems we need to verify." It's understandable that a company flying people into space would be cautious. Any accidents would undoubtedly put a damper on customer enthusiasm. (submitted by danneely and Ken the Bin)

Virgin Orbit ships rocket to launch site. Virgin said this week that it has shipped the rocket that will fly its first mission into space from the company's factory in Long Beach. At its test site in Mojave, the company says it will begin the rocket's launch campaign. A launch could come late in 2019, provided testing goes well.

Off to the skies ... "In the coming weeks, we'll run through a number of critical exercises, including loading and fueling with our mobile ground-support equipment," Virgin said. "We are prepping and practicing, making sure we know how to do everything we could conceivably ever need to do. Then, it's off to the skies—first for a captive carry flight, and then for the launch itself." We're eager to see LauncherOne take to the skies. (submitted by Unrulycow)

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Firefly releases updated Payload User's Guide. At first glance, the document appears to contain few significant changes. The Alpha rocket, with a maximum capacity of 1 ton to low Earth orbit, is still being offered to customers for $15 million a launch. The guide also provides information about the larger Beta rocket under development, but it does not provide a price.

Ongoing stage tests ... Meanwhile, Firefly has continued to conduct a series of stage tests for the Alpha vehicle. The company indicated last week that it had put a full cluster of four Reaver 1 engines on a test stand in Texas, in the same configuration as for an Alpha launch. The first Firefly mission now appears likely to launch sometime during the first quarter of 2020 from Vandenberg Air Force Base. (submitted by Unrulycow)

Water plasma propulsion shows promise. Silicon Valley startup Momentus says it has had success in on-orbit testing of water plasma propulsion and other key elements of its Vigoride in-space transportation vehicle, SpaceNews reports. Since July, the company has been firing the water plasma thruster and performing in-space maneuvers on a 16-unit Cubesat.

Early results are promising ... "This successfully demonstrates for the first time in-space water plasma propulsion, and also demonstrates the technology, which has the highest specific impulse among other water-based propulsion," the company said. One promising application for the technology is moving satellites from the orbit where they are dropped off by large rockets conducting rideshare missions to their optimal orbital locations. On-orbit testing will continue.

Soyuz FG makes final ride into space. The venerable Soyuz FG rocket launched for the 70th time on Wednesday, lofting Oleg Skripochka (Russia), Jessica Meir (United States), and Hazzaa Al Mansouri (United Arab Emirates) to the International Space Station. The Soyuz FG variant served as a bridge between the older Soyuz-U and the newer Soyuz 2 rocket variants, NASASpaceFlight.com reports. The FG launched for the first time in May 2001.

Served NASA and the Russians well ... The Soyuz FG has been the only Russian rocket to launch humans to the International Space Station for the last 17 years, and since the retirement of the US Space Shuttle fleet in July 2011, it has been the only rocket capable of transporting people to the International Space Station. The rocket's only failure came in 2018, when the crew had to make an emergency landing.

Japanese rocket safely launches after pad issue. A Japanese H-2B rocket flew into orbit Tuesday from the Tanegashima Space Center, Spaceflight Now reports. The automated cargo freighter was loaded with 4.1 tons of batteries, experiments, spacewalk equipment, water, and provisions for the International Space Station.

Surviving a fire ... The launch followed a first attempt September 10, when a dramatic fire on the launchpad halted the countdown. Officials determined the fire was likely caused by static electricity and high concentrations of oxygen that dripped from the rocket's main engines during the September 10 countdown. After instituting unspecific "corrective actions," Mitsubishi Heavy Industries returned the H-2B rocket to the launchpad a half-day before Tuesday's launch to begin a new countdown. (submitted by Ken the Bin)

Falcon Heavy rocket is now fully certified. Now that the Falcon Heavy rocket built by SpaceX has flown three flights, it is "fully certified" for Air Force missions. However, work remains to make the vehicle eligible to fly missions to all of the Department of Defense's reference orbits, Lt. Gen. John Thompson, commander of the Air Force Space and Missile Systems Center, told SpaceNews.

More work to go ... "It's not certified for all of our most stressing national security space orbits," Gen. Thompson said. "We continue to work with SpaceX to mature their design, and I think that's going well." Launch vehicle systems are certified for specific mass and orbit combinations. Eventually, the Falcon Heavy is likely to be certified for all nine of the DOD reference orbits. (submitted by Ken the Bin and Unrulycow)

Senate budget fully funds Exploration Upper Stage. The US Senate has continued to make its priorities for NASA clear, as budget writers provided $2.586 billion for the Space Launch System, which is more than $400 million above 2019 levels. The additional SLS funding includes $300 million for work on the Exploration Upper Stage planned for the Block 1B version of the SLS, funding that the administration did not seek in its original funding request, SpaceNews reports.

A message from Shelby ... At the same time, the Senate budget provides $744 million for lunar landers, well short of the $1 billion NASA said it needed to keep the Artemis Program on track to send humans to the Moon by 2024. This appears to be Senate Appropriations Committee Chairman Richard Shelby's (R-Ala.) not-so-subtle way of reminding NASA who is really in charge of the agency.

Riding home from space in the shuttle's payload bay. In a blog post this week, former space shuttle program manager Wayne Hale shared a delightful story about emergency plans, which were never used, to bring home an astronaut inside the space shuttle's payload bay. It's quite a read.

Wait, really? ... "There was a good place to strap down at the bottom of the payload bay aft of the SpaceLab module. It would be a short wait from finishing up with the doors until the de-orbit burn, probably no more than an hour and a half. From de-orbit burn to the ground was about an hour, and in normal flight the g loading was light, nothing more than 1.5g."

Another thing to consider with CoG is that in later iterations with refined production process, they expect the whole thing to be MUCH lighter dry, so the reasons to have extra ballast at the nose for Mk 1 & 2 might not exist

edit, the fairing area will need to be reinforced in comparison to the prop tank area anyways, as it doesn't have the tank pressure to back it while it is going through the sound barrier, so this may provide a natural ballast if the header tanks return to the inside of the LOX tank

Doesn't that go the opposite direction? If you figure the engines aren't going to go on a diet and the rest of the structure loses 40% of its mass across the board, then the cg is going to be lower in the future.

most of the metal is in the prop tanks, however without the prop to support it, the upper half cant go on as significant of a diet,

Meanwhile on the Boca Chica ranch: both canards (and flaps) are installed, the thing is awaiting mating!

Spoiler: show

Wow, those canards are further forward than I expected (like, they can't get any further forward than that)! I guess that gives them the maximum control moment, but it does look a bit odd.

Whatever works, I guess.

They've put the header tanks and battery packs and other stuff in the nose section for CG balance, so there will be significant stiffening structures inside to carry this stuff plus the loads from the forward flaps. In this iteration at least, it seems that the middle section between the nose section and the main prop tank is the payload section, and they don't want to have significant vehicle hardware intruding into this volume.

The Musk tweet "upskirt" pic showing the three installed Raptors also showed the crazy amount of reinforcing in the bottom part of SS below the conical lower tank bottom bulkhead. It then seems a lot less crazy when you remember it has to support the full weight of a fuelled SS being accelerated by a 37 Raptor SH without internal pressurization and subject to lateral vibrations of approaching 1g. That is on the order of 5000 tons of force carried axially and maybe 1000+ tons lateral transients. The top of this section has the outside reinforcing band added to keep the conical bulkhead from splitting it.

Dang, I love the juxtaposition here with the amazing complexity and precision of the engine bay, compared to the crude looking exterior.

Not that I'm knockinging the exterior. I love the look of the Starship, and with the foils way up front it's even more visually interesting than the 3D mockups SpaceX has presented in the past. As a kid, I was always a little disappointed in how boring most modern rockets looked, especially when compared to the Shuttle, and this is an awesome break from tradition.

[Dang, I love the juxtaposition here with the amazing complexity and precision of the engine bay, compared to the crude looking exterior.

Not that I'm knockinging the exterior. I love the look of the Starship, and with the foils way up front it's even more visually interesting than the 3D mockups SpaceX has presented in the past. As a kid, I was always a little disappointed in how boring most modern rockets looked, especially when compared to the Shuttle, and this is an awesome break from tradition.

dont expect it in final version, the build process that results in that look is adding a LOT of drymass it is just being used because it is quick and cheap

For thermal reasons I would think that the headers in the main tanks, that and saving mass, might put some RCS tanks up top, which may be warm CH4, but the high pressure feed into the engines going that distance will not be light, and for Mars they need the header tanks to stay cool for months, it will be easier to do that inside the main prop tank.

I used to agree with this argument, but then I realized that the main tanks will either be mostly empty or completely empty and vented to vacuum during the Mars coast, so it's not like the header tanks are going to be submerged in cryogenic propellant during that time. It would be like a vacuum-insulated thermos. With the header tanks installed inside a nose cone which is vented to vacuum, it'll be pretty much the same thermos effect. The nose cone is exposed to radiative heating, but the header tanks inside are not, because there's a double wall with vacuum in between.

The downcomer pipes from the header tanks in the nose and their covers are heavy but they might have wanted the effective chine shape for aerodynamics anyway so it the weight penalty is offset. It will be interesting to see if they keep this configuration in later versions.

IIRC Musk said that the header tanks, etc, are only in the nose for these prototypes for weight and balance reasons, to offset the weight of the engines. They will be moved back to the main tanks when other gear (more avionics, payload structures, life support, whatever) is installed forward in production.

Of course that may change just as the number of fins and almost everything else about SS has.

For thermal reasons I would think that the headers in the main tanks, that and saving mass, might put some RCS tanks up top, which may be warm CH4, but the high pressure feed into the engines going that distance will not be light, and for Mars they need the header tanks to stay cool for months, it will be easier to do that inside the main prop tank.

I used to agree with this argument, but then I realized that the main tanks will either be mostly empty or completely empty and vented to vacuum during the Mars coast, so it's not like the header tanks are going to be submerged in cryogenic propellant during that time. It would be like a vacuum-insulated thermos. With the header tanks installed inside a nose cone which is vented to vacuum, it'll be pretty much the same thermos effect. The nose cone is exposed to radiative heating, but the header tanks inside are not, because there's a double wall with vacuum in between.

The downcomer pipes from the header tanks in the nose and their covers are heavy but they might have wanted the effective chine shape for aerodynamics anyway so it the weight penalty is offset. It will be interesting to see if they keep this configuration in later versions.

IIRC Musk said that the header tanks, etc, are only in the nose for these prototypes for weight and balance reasons, to offset the weight of the engines. They will be moved back to the main tanks when other gear (more avionics, payload structures, life support, whatever) is installed forward in production.

Of course that may change just as the number of fins and almost everything else about SS has.

Apparently the Raptors in SS are dev and test units for fit testing as well as Elon's show and will be replaced before first flight. That makes me relax a bit about the slight dent on the bottom edge of one of the nozzle bells. :-P

That said one of the control surfaces was photo'd a while back with numbering indicating an aluminum alloy on a portion of it. That might also be a temp for fit and show. We may get all stainless steel units before flight. Or at least flights with significant re-entry heating.

For thermal reasons I would think that the headers in the main tanks, that and saving mass, might put some RCS tanks up top, which may be warm CH4, but the high pressure feed into the engines going that distance will not be light, and for Mars they need the header tanks to stay cool for months, it will be easier to do that inside the main prop tank.

I used to agree with this argument, but then I realized that the main tanks will either be mostly empty or completely empty and vented to vacuum during the Mars coast, so it's not like the header tanks are going to be submerged in cryogenic propellant during that time. It would be like a vacuum-insulated thermos. With the header tanks installed inside a nose cone which is vented to vacuum, it'll be pretty much the same thermos effect. The nose cone is exposed to radiative heating, but the header tanks inside are not, because there's a double wall with vacuum in between.

The downcomer pipes from the header tanks in the nose and their covers are heavy but they might have wanted the effective chine shape for aerodynamics anyway so it the weight penalty is offset. It will be interesting to see if they keep this configuration in later versions.

IIRC Musk said that the header tanks, etc, are only in the nose for these prototypes for weight and balance reasons, to offset the weight of the engines. They will be moved back to the main tanks when other gear (more avionics, payload structures, life support, whatever) is installed forward in production.

Of course that may change just as the number of fins and almost everything else about SS has.

Apparently the Raptors in SS are dev and test units for fit testing as well as Elon's show and will be replaced before first flight. That makes me relax a bit about the slight dent on the bottom edge of one of the nozzle bells. :-P

That said one of the control surfaces was photo'd a while back with numbering indicating an aluminum alloy on a portion of it. That might also be a temp for fit and show. We may get all stainless units before flight. Or at least flights with significant re-entry heating.

I suspect the AL control surfaces were outsourced from someone who does aircraft wings, and already had the equipment set up to do it in AL, for testing the flight characteristics and aerodynamics it doesnt matter that it isnt stainless, they dont need to be stainless until they are stacking it ontop of SH

For thermal reasons I would think that the headers in the main tanks, that and saving mass, might put some RCS tanks up top, which may be warm CH4, but the high pressure feed into the engines going that distance will not be light, and for Mars they need the header tanks to stay cool for months, it will be easier to do that inside the main prop tank.

I used to agree with this argument, but then I realized that the main tanks will either be mostly empty or completely empty and vented to vacuum during the Mars coast, so it's not like the header tanks are going to be submerged in cryogenic propellant during that time. It would be like a vacuum-insulated thermos. With the header tanks installed inside a nose cone which is vented to vacuum, it'll be pretty much the same thermos effect. The nose cone is exposed to radiative heating, but the header tanks inside are not, because there's a double wall with vacuum in between.

The downcomer pipes from the header tanks in the nose and their covers are heavy but they might have wanted the effective chine shape for aerodynamics anyway so it the weight penalty is offset. It will be interesting to see if they keep this configuration in later versions.

IIRC Musk said that the header tanks, etc, are only in the nose for these prototypes for weight and balance reasons, to offset the weight of the engines. They will be moved back to the main tanks when other gear (more avionics, payload structures, life support, whatever) is installed forward in production.

Of course that may change just as the number of fins and almost everything else about SS has.

Apparently the Raptors in SS are dev and test units for fit testing as well as Elon's show and will be replaced before first flight. That makes me relax a bit about the slight dent on the bottom edge of one of the nozzle bells. :-P

That said one of the control surfaces was photo'd a while back with numbering indicating an aluminum alloy on a portion of it. That might also be a temp for fit and show. We may get all stainless units before flight. Or at least flights with significant re-entry heating.

I suspect the AL control surfaces were outsourced from someone who does aircraft wings, and already had the equipment set up to do it in AL, for testing the flight characteristics and aerodynamics it doesnt matter that it isnt stainless, they dont need to be stainless until they are stacking it ontop of SH

I suspect the higher energy sub-orbital tests will need SS as well. You're right that the initial low energy flights won't have any significant thermal loads to worry about.

I see Richard Shelby continues his reign of terror, holding Space program hostage to his and his state's political whims.

I so want see that guy removed from office, heck i could see the president getting tired of his programs being mucked up by this opportunist trying get pork for his state.

Shelby could put Trump in a complete rage and there's not a thing Trump could do. One gets 'removed from office' by being voted out. That's what the pork is all about. The only way to get Shelby out of power in his committee is for the Senate to go majority Democrat. He'll be a Senator until he goes belly-up in his office.

For thermal reasons I would think that the headers in the main tanks, that and saving mass, might put some RCS tanks up top, which may be warm CH4, but the high pressure feed into the engines going that distance will not be light, and for Mars they need the header tanks to stay cool for months, it will be easier to do that inside the main prop tank.

I used to agree with this argument, but then I realized that the main tanks will either be mostly empty or completely empty and vented to vacuum during the Mars coast, so it's not like the header tanks are going to be submerged in cryogenic propellant during that time. It would be like a vacuum-insulated thermos. With the header tanks installed inside a nose cone which is vented to vacuum, it'll be pretty much the same thermos effect. The nose cone is exposed to radiative heating, but the header tanks inside are not, because there's a double wall with vacuum in between.

The downcomer pipes from the header tanks in the nose and their covers are heavy but they might have wanted the effective chine shape for aerodynamics anyway so it the weight penalty is offset. It will be interesting to see if they keep this configuration in later versions.

IIRC Musk said that the header tanks, etc, are only in the nose for these prototypes for weight and balance reasons, to offset the weight of the engines. They will be moved back to the main tanks when other gear (more avionics, payload structures, life support, whatever) is installed forward in production.

Of course that may change just as the number of fins and almost everything else about SS has.

That said one of the control surfaces was photo'd a while back with numbering indicating an aluminum alloy on a portion of it. That might also be a temp for fit and show. We may get all stainless steel units before flight. Or at least flights with significant re-entry heating.

The aluminum alloy part was a rib. The skins of the flaps are stainless. We'll see if they take these flaps off and replace them before they start flying lofted suborbital trajectories with high reentry velocities. With thermal protection tiles on the windward side of the flaps, there might not be enough heat flux into the internal rib structure to cause problems with the aluminum alloy, but I would not be shocked to see these flaps replaced.

For thermal reasons I would think that the headers in the main tanks, that and saving mass, might put some RCS tanks up top, which may be warm CH4, but the high pressure feed into the engines going that distance will not be light, and for Mars they need the header tanks to stay cool for months, it will be easier to do that inside the main prop tank.

I used to agree with this argument, but then I realized that the main tanks will either be mostly empty or completely empty and vented to vacuum during the Mars coast, so it's not like the header tanks are going to be submerged in cryogenic propellant during that time. It would be like a vacuum-insulated thermos. With the header tanks installed inside a nose cone which is vented to vacuum, it'll be pretty much the same thermos effect. The nose cone is exposed to radiative heating, but the header tanks inside are not, because there's a double wall with vacuum in between.

The downcomer pipes from the header tanks in the nose and their covers are heavy but they might have wanted the effective chine shape for aerodynamics anyway so it the weight penalty is offset. It will be interesting to see if they keep this configuration in later versions.

IIRC Musk said that the header tanks, etc, are only in the nose for these prototypes for weight and balance reasons, to offset the weight of the engines. They will be moved back to the main tanks when other gear (more avionics, payload structures, life support, whatever) is installed forward in production.

Of course that may change just as the number of fins and almost everything else about SS has.

That said one of the control surfaces was photo'd a while back with numbering indicating an aluminum alloy on a portion of it. That might also be a temp for fit and show. We may get all stainless steel units before flight. Or at least flights with significant re-entry heating.

The aluminum alloy part was a rib. The skins of the flaps are stainless. We'll see if they take these flaps off and replace them before they start flying lofted suborbital trajectories with high reentry velocities. With thermal protection tiles on the windward side of the flaps, there might not be enough heat flux into the internal rib structure to cause problems with the aluminum alloy, but I would not be shocked to see these flaps replaced.

At only 10 minutes for the total re-entry, it's possible the temperature may not peak high enough on the internal ribs to bother with steel.

For thermal reasons I would think that the headers in the main tanks, that and saving mass, might put some RCS tanks up top, which may be warm CH4, but the high pressure feed into the engines going that distance will not be light, and for Mars they need the header tanks to stay cool for months, it will be easier to do that inside the main prop tank.

The nose-mounted header tanks can be dewars which eliminates most of the need for insulation. Dewars that size for long-term LOX storage are commercially available at very low cost and reasonable weight. For Mars they probably want custom ones but that's still reasonably cheap.

The long pipe run down the vehicle increases the head pressure, which reduces the operating pressure in the headers, which reduces the mass of the tank. Putting the header tank volume in the nose reduces the main tank volume proportionally, which shortens the tanks and thus increases the full-width length of the cargo bay for a given vehicle length, which makes it a more useful shape for cargo.

Meanwhile on the Boca Chica ranch: both canards (and flaps) are installed, the thing is awaiting mating!

Spoiler: show

Wow, those canards are further forward than I expected (like, they can't get any further forward than that)! I guess that gives them the maximum control moment, but it does look a bit odd.

Whatever works, I guess.

They've put the header tanks and battery packs and other stuff in the nose section for CG balance, so there will be significant stiffening structures inside to carry this stuff plus the loads from the forward flaps. In this iteration at least, it seems that the middle section between the nose section and the main prop tank is the payload section, and they don't want to have significant vehicle hardware intruding into this volume.

The Musk tweet "upskirt" pic showing the three installed Raptors also showed the crazy amount of reinforcing in the bottom part of SS below the conical lower tank bottom bulkhead. It then seems a lot less crazy when you remember it has to support the full weight of a fuelled SS being accelerated by a 37 Raptor SH without internal pressurization and subject to lateral vibrations of approaching 1g. That is on the order of 5000 tons of force carried axially and maybe 1000+ tons lateral transients. The top of this section has the outside reinforcing band added to keep the conical bulkhead from splitting it.

I'm a bit surprised they didn't chop the lee half of that away and put it on SuperHeavy, like they did for the initial ITS concept. That's probably ~5 t of structure that they don't have to haul to orbit and back.

Me neither. It's possible there's a man portal on the back side. Or else they have an egress down somehow.

Have they capped off the nose cone yet? While it was on the ground I know they lowered people down the hole on the tip to get inside, if that's still open they could lift the workers out that way using the crane as a massively oversized hoist.

Me neither. It's possible there's a man portal on the back side. Or else they have an egress down somehow.

Have they capped off the nose cone yet? While it was on the ground I know they lowered people down the hole on the tip to get inside, if that's still open they could lift the workers out that way using the crane as a massively oversized hoist.

Nose cone doesn't appear to be capped. So there may be a ladder inside.

Meanwhile on the Boca Chica ranch: both canards (and flaps) are installed, the thing is awaiting mating!

Spoiler: show

Wow, those canards are further forward than I expected (like, they can't get any further forward than that)! I guess that gives them the maximum control moment, but it does look a bit odd.

Whatever works, I guess.

They've put the header tanks and battery packs and other stuff in the nose section for CG balance, so there will be significant stiffening structures inside to carry this stuff plus the loads from the forward flaps. In this iteration at least, it seems that the middle section between the nose section and the main prop tank is the payload section, and they don't want to have significant vehicle hardware intruding into this volume.

The Musk tweet "upskirt" pic showing the three installed Raptors also showed the crazy amount of reinforcing in the bottom part of SS below the conical lower tank bottom bulkhead. It then seems a lot less crazy when you remember it has to support the full weight of a fuelled SS being accelerated by a 37 Raptor SH without internal pressurization and subject to lateral vibrations of approaching 1g. That is on the order of 5000 tons of force carried axially and maybe 1000+ tons lateral transients. The top of this section has the outside reinforcing band added to keep the conical bulkhead from splitting it.

I'm a bit surprised they didn't chop the lee half of that away and put it on SuperHeavy, like they did for the initial ITS concept. That's probably ~5 t of structure that they don't have to haul to orbit and back.

The final version might, depending on how the legs attach. For an early test model that's seriously overweight everywhere it's not a big deal; and being radially symmetric simplifies moving it around.

So is that where it's going to launch from or will they be able to crane lift it from the top once it's all welded together?

They'd use a heavy lift mover under it for that.

Ok, can't see that from the video. So they have a mobile launch platform basically?

They rent Roll-Lift vehicles to move Starship. They used them to roll the main tank section from its assembly area to the current display position. Crane lifts the vehicle on and off the Roll-Lifts. It's a relatively expensive rental which requires its own operating crews etc, so they only have them on site when they need them.

As for launch platform, we know that for Starship-only launches they're going to use a tall launch fixture to elevate the vehicle above the surface. For Super Heavy they'll have a water-cooled flame diverter evolved from similar setups at the McGregor "Large Site" and the post-AMOS-6 rebuild of LC-40.

Another thing to consider with CoG is that in later iterations with refined production process, they expect the whole thing to be MUCH lighter dry, so the reasons to have extra ballast at the nose for Mk 1 & 2 might not exist

edit, the fairing area will need to be reinforced in comparison to the prop tank area anyways, as it doesn't have the tank pressure to back it while it is going through the sound barrier, so this may provide a natural ballast if the header tanks return to the inside of the LOX tank

Doesn't that go the opposite direction? If you figure the engines aren't going to go on a diet and the rest of the structure loses 40% of its mass across the board, then the cg is going to be lower in the future.

Well right now the engine are probably about 2% of the total mass, so they aren't going to be driving the CG much compared to other changes.

So is that where it's going to launch from or will they be able to crane lift it from the top once it's all welded together?

They'd use a heavy lift mover under it for that.

Ok, can't see that from the video. So they have a mobile launch platform basically?

They rent Roll-Lift vehicles to move Starship. They used them to roll the main tank section from its assembly area to the current display position. Crane lifts the vehicle on and off the Roll-Lifts. It's a relatively expensive rental which requires its own operating crews etc, so they only have them on site when they need them.

So it's crane-liftable in the final assembled orientation then - minus propellant of course.